What kind of business do you have? The Turbo Tax Business program is only a Desktop program for Windows. Or did you use the online Self Employed version?
If you used the Business program or the personal Home & Business program your return is only on your computer and not online.
Open your program and go to File-Open. Your return ends in .tax2019 and should be in your Documents then in a Turbo Tax folder. Did you save it? In Windows you have to save it each time.
